<template>
  <div>
    <div class="mask" v-show="isShowSelect" @click="isShowSelect = !isShowSelect"></div>
    <el-popover placement="bottom-start" :width="width" trigger="manual" v-model="isShowSelect" @hide="popoverHide"
      popper-class="tree-popover" :disabled="isAddState == '0'">
      <el-tree class="common-tree" :style="style" ref="tree" :data="data" :props="defaultProps"
        :default-expanded-keys="['省产业数字化发展部']" :show-checkbox="multiple" :node-key="nodeKey" :check-strictly="checkStrictly"
        :default-checked-keys="defaultCheckedKeys" :highlight-current="true" @node-click="handleNodeClick"
        @check-change="handleCheckChange" :disabled="isAddState == '0'"></el-tree>
      <el-select slot="reference" ref="select" :disabled="isAddState == '0'" v-model="selectedData"
        @clear="resetChecked" clearable :multiple="multiple" @click.native="isShowSelect = !isShowSelect"
        class="tree-select">
        <el-option v-for="item in options" :key="item.value" :label="item.label" :value="item.value"></el-option>
      </el-select>
    </el-popover>
  </div>
</template>

<script>
export default {
  name: 'tree-select',
  props: {
    // 树结构数据
    isAddState: {
      type: String,
      default() {
        return '1';
      }
    },
    data: {
      type: Array,
      default() {
        return [];
      }
    },
    defaultProps: {
      type: Object,
      default() {
        return {};
      }
    },
    // 配置是否可多选
    multiple: {
      type: Boolean,
      default() {
        return false;
      }
    },
    nodeKey: {
      type: String,
      default() {
        return 'id';
      }
    },
    // 显示复选框情况下，是否严格遵循父子不互相关联
    checkStrictly: {
      type: Boolean,
      default() {
        return false;
      }
    },
    // 默认选中的节点key数组
    checkedKeys: {
      type: Array,
      default() {
        return [];
      }
    },
    width: {
      type: Number,
      default() {
        return 235;
      }
    },
    height: {
      type: Number,
      default() {
        return 300;
      }
    }
  },
  data() {
    return {
      defaultCheckedKeys: [],
      isShowSelect: false, // 是否显示树状选择器
      options: [],
      selectedData: this.multiple ? [] : '', // 选中的节点
      style: 'width:' + (this.width - 26) + 'px;' + 'max-height:' + this.height + 'px;',
      selectStyle: 'width:' + this.width + 'px;',
      checkedIds: [],
      checkedData: []
    };
  },
  mounted() {
    this.checkedTree()
  },
  methods: {
    checkedTree() {
      if (this.checkedKeys.length > 0) {
        if (this.multiple) {
          this.defaultCheckedKeys = this.checkedKeys;
          this.selectedData = this.checkedKeys.map((item) => {
            var node = this.$refs.tree.getNode(item);
            return node.label;
          });
        } else {
          var item = this.checkedKeys[0];
          this.$refs.tree.setCurrentKey(item);
          var node = this.$refs.tree.getNode(item);
          this.selectedData = node.label;
        }
      }
    },
    resetChecked() {
      if (this.multiple) {
        this.$refs.tree.setCheckedKeys([]);
        this.$emit('popoverHide', [], {});
      } else {
        this.$refs.tree.setCurrentKey(null);
        this.$emit('popoverHide', '', {});
      }
    },
    popoverHide() {
      if (this.multiple) {
        this.checkedIds = this.$refs.tree.getCheckedKeys(); // 所有被选中的节点的 key 所组成的数组数据
        this.checkedData = this.$refs.tree.getCheckedNodes(); // 所有被选中的节点所组成的数组数据
      } else {
        this.checkedIds = this.$refs.tree.getCurrentKey();
        this.checkedData = this.$refs.tree.getCurrentNode();
      }
      this.$emit('popoverHide', this.checkedIds, this.checkedData);
    },
    // 节点被点击时的回调,返回被点击的节点数据
    handleNodeClick(data, node) {
      if (!this.multiple) {
        if (!data.haveChildren) {
          let tmpMap = {};
          tmpMap.value = node.key;
          tmpMap.label = node.label;
          this.options = [];
          this.options.push(tmpMap);
          this.selectedData = node.label;
          this.isShowSelect = !this.isShowSelect;
        }
      }
    },
    // 节点选中状态发生变化时的回调
    handleCheckChange() {
      var checkedKeys = this.$refs.tree.getCheckedKeys(); // 所有被选中的节点的 key 所组成的数组数据
      this.options = checkedKeys.map((item) => {
        var node = this.$refs.tree.getNode(item); // 所有被选中的节点对应的node
        let tmpMap = {};
        tmpMap.value = node.key;
        tmpMap.label = node.label;
        return tmpMap;
      });
      this.selectedData = this.options.map((item) => {
        return item.label;
      });
    }
  },
  watch: {
    isShowSelect(val) {
      // 隐藏select自带的下拉框
      this.$refs.select.blur();
    },
    checkedKeys(val, oldVal) {
      if (val !== oldVal) {
        this.checkedTree()
        if (!val.length) {
          this.resetChecked()
          this.selectedData = ''
        }
      }
    },
  }
};
</script>

<style scoped>
.mask {
  width: 100%;
  height: 100%;
  position: fixed;
  top: 0;
  left: 0;
  opacity: 0;
  z-index: 1;
}

/* .common-tree {
  overflow: auto;
} */
</style>

<style>
.tree-select .el-select__tags .el-tag .el-tag__close {
  display: none;
}

.tree-select .el-select__tags .el-tag .el-icon-close {
  display: none;
}

.tree-popover {
  overflow-y: auto;
  overflow-x: hidden;
}
</style>
